Javascript AngularJS在指令模板中使用画布
我正在尝试使用Javascript AngularJS在指令模板中使用画布,javascript,angularjs,canvas,angularjs-directive,Javascript,Angularjs,Canvas,Angularjs Directive,我正在尝试使用指令使用画布实现进度条 我希望elrady通过JS对象实现这个控件 以下是非角度方式: function progressBar(id,contentDiv) { this.id = id; this.height = 2; this.width = 200; this.backColor = "#383838"; this.foreColor = "#61650c"; this.value = 0; this.context
指令使用画布实现进度条
我希望elrady通过JS对象实现这个控件
以下是非角度方式:
function progressBar(id,contentDiv)
{
this.id = id;
this.height = 2;
this.width = 200;
this.backColor = "#383838";
this.foreColor = "#61650c";
this.value = 0;
this.context = null;
this.backToZero = true;
this.create = function ()
{
var str = "";
str += "<div class='progressBarDiv' id='" + this.id + "' style='width: " + this.width + "px;'>";
str += "<canvas id='canvas_" + this.id + "' class='progressBarCanvas' width='" + this.width + "' height='" + this.height + "' style='width: " + this.width + "px;'/>";
str += "</div>";
$("#" + contentDiv).html(str);
this.drawingCanvas = document.getElementById('canvas_' + this.id);
this.context = this.drawingCanvas.getContext('2d');
this.draw();
}
this.draw = function ()
{
var ctx = this.context;
ctx.fillStyle = this.backColor;
ctx.fillRect(0, 0, this.width, this.height);
var pos = this.value / 100 * this.width;
ctx.fillStyle = this.foreColor;
ctx.fillRect(0, 0, pos, this.height);
}
this.setValue = function (value)
{
this.value = value;
if (value >= 100)
{
if (this.backToZero)
{
this.value = 0;
}
}
this.draw();
}
}
函数进度条(id,contentDiv)
{
this.id=id;
这个高度=2;
这个宽度=200;
this.backColor=“#3838”;
this.foreColor=“#61650c”;
该值=0;
this.context=null;
this.backToZero=true;
this.create=函数()
{
var str=“”;
str+=”;
str+=”;
str+=”;
$(“#”+contentDiv.html(str);
this.drawingCanvas=document.getElementById('canvas_u'+this.id);
this.context=this.drawingCanvas.getContext('2d');
这个.draw();
}
this.draw=函数()
{
var ctx=this.context;
ctx.fillStyle=this.backColor;
ctx.fillRect(0,0,this.width,this.height);
var pos=此值/100*此宽度;
ctx.fillStyle=此.foreColor;
ctx.fillRect(0,0,位置,此高度);
}
this.setValue=函数(值)
{
这个值=值;
如果(值>=100)
{
如果(此返回零)
{
该值=0;
}
}
这个.draw();
}
}
我试着用角度指令做同样的事情。
以下是我迄今为止的情况:
KApp.directive("kProgress", function ()
{
return {
restrict: 'E',
scope: {
progressStatus: '=progress',
progressWidth:'@',
progressHeight:'@',
progressId:'@'
},
template: "<div class='progressBarDiv' style='width: " + {{progressWidth}} + "px;'>"
+"<canvas id='canvas_" + {{progressId}} + "' class='progressBarCanvas' width='" + {{progressWidth}} + "' height='" + {{progressHeight}} + "' style='width: " + {{progressWidth}} + "px;'/>"
+"</div>",
link: function(scope, element, attrs) {
scope.$watch(attrs.progressStatus, function(value) {
//Change the canvas (from the template)
});
}
};
});
KApp.指令(“kProgress”,函数()
{
返回{
限制:'E',
范围:{
progressStatus:'=进度',
progressWidth:“@”,
progressHeight:“@”,
progressId:“@”
},
模板:“”
+""
+"",
链接:函数(范围、元素、属性){
范围$watch(attrs.progressStatus,函数(值){
//更改画布(从模板)
});
}
};
});
我的问题是:如何从模板中获取(或访问)canvas元素,并根据progressStatus
属性(从外部控制器提交)对其进行操作。我需要kProgress
指令的作用与非角度解决方案完全相同。这是一个直接的用例,请参阅“创建通信指令”部分 我认为您上面的主要问题是您正在观看的是attrs.progressStatus
,而不仅仅是progressStatus
。这项工作:
var module = angular
.module('progressBarApp', [])
.directive("progressBar", function ()
{
return {
restrict: 'E',
scope: {
progress: '=',
progressId: '@'
},
template: "<canvas id='pgcanvas' width='400' height='30' background-color: #F00'/>",
link: function(scope, element, attrs) {
console.log(element);
scope.canvas = element.find('canvas')[0];
scope.context = scope.canvas.getContext('2d');
scope.$watch('progress', function(newValue) {
barWidth = Math.ceil(newValue / 100 * scope.canvas.width);
scope.context.fillStyle = "#DDD";
scope.context.fillRect(0, 0, scope.canvas.width, scope.canvas.height);
scope.context.fillStyle = "#F00";
scope.context.fillRect(0, 0, barWidth, scope.canvas.height);
});
}
};
});
var模块=角度
.module('progressBarApp',[])
.指令(“progressBar”,函数()
{
返回{
限制:'E',
范围:{
进度:'=',
progressId:“@”
},
template:“这不一样!我不需要与另一个指令“通信”,我只需要与模板中的元素“通信”您是否尝试过element.find()?并尝试postLink函数。